Solar concentrators are solar energy generators which increase the efficiency of converting solar energy into DC electricity. Solar concentrators known in the art utilize, for example, parabolic mirrors and Fresnel lenses for focusing incoming solar energy, and heliostats for tracking the sun's movements in order to maximize light exposure. Another type of solar concentrator, disclosed in U.S. Patent Publication No. 2006/0266408, entitled “Concentrator Solar Photovoltaic Array with Compact Tailored Imaging Power Units,” utilizes a front panel for allowing solar energy to enter the assembly, with a primary mirror and a secondary mirror to reflect and focus solar energy through a non-imaging concentrator onto a solar cell. The surface area of the solar cell in such a concentrator system is much smaller than what is required for non-concentrating systems, for example less than 1% of the entry window surface area. Such a system has a high efficiency in converting solar energy to electricity due to the focused intensity of sunlight, and also reduces cost due to the decreased surface area of costly photovoltaic cells.
A similar type of solar concentrator is disclosed in U.S. Patent Publication No. 2006/0207650, entitled “Multi-Junction Solar Cells with an Aplanatic Imaging System and Coupled Non-Imaging Light Concentrator.” The solar concentrator design disclosed in this application uses a solid optic, out of which a primary mirror is formed on its bottom surface and a secondary mirror is formed in its upper surface. Solar radiation enters the upper surface of the solid optic, reflects from the primary mirror surface to the secondary mirror surface, and then enters a non-imaging concentrator which outputs the light onto a photovoltaic solar cell.
Solar concentrators of this type and others are typically assembled into arrays for producing energy at commercial levels. An array may be housed in an enclosure, which serves to protect the solar concentrator modules from environmental conditions and to provide structural support for transporting and mounting the array. Enclosures for solar concentrator arrays generally come in the form of a flat-bottomed back panel to hold the components of the array, with a glass front sheet covering the top for transmitting light and completing the enclosure. Because such box-type back panels, or “backpans,” provide a simple design which is easy to manufacture, there is little motivation to stray from their use. Standard flat backpans are cost-effective, provide adequate structural support, and offer sufficient weather resistance for a solar concentrator array. Yet, there exists an undeveloped opportunity to create a backpan which not only provides structural support and protection, but that also provides functional and manufacturing advantages to the operation of a solar concentrator array.